Further studies have been carried out on the immunologic mechanisms involved in the induction and prevention of cell-mediated immunity to myelin basic protein: induction, prevention, suppression and treatment of experimental allergic encephalomyelitis (EAE). Our previous hypothesis that the structural requirements for prevention of EAE are the same as those for induction has been confirmed. The ability of purified basic protein to prevent the disease induced by whole CNS has also confirmed our hypothesis that BP is the only constituent of CNS tissue which is capable of inducing EAE. BIBLIOGRAPHIC REFERENCES: Alvord, E.C., Jr., Hruby, S., Petersen, R. and Kies, M.W.: An analysis of antigenic determinants within myelin membrane encephalitogenic protein. In Shiraki, H., Yonezawa, T. and Kuroiwa, Y. (Eds.): The Aetiology and Pathogenesis of the Demyelinating Diseases. Tokoyo, Japan Science Press, 1976, pp. 217-226. Driscoll, B. F., Kies, M.W. and Alvord, E.C., Jr.: Protection against experimental allergic encephalomyelitis with peptides derived from myelin basic protein: presence of intact encephalitogenic site is essential. J. Immunol. 117: 110-114, 1976.